RASTER SCANNER ALIGNMENT TECHNIQUE
Original Publication Date: 1980-Jun-30
Included in the Prior Art Database: 2004-Apr-02
Xerox Disclosure Journal
Both the sagittal (in the Y-direction) and tangential (in the X-direction) misalignments between the scanning arrays of a raster scanner can be overcome by properly choosing the array offsets along the Y-axis for the former and the bit offset(s) along the X-axis for the latter. This can be accomplished using a test document or fixed targets at the perimeter of the viewing platen, specifically designed for misalignment adjustments and an initialization routine. During initialization, the scanner reads the input; i.e., the test document and determines the necessary offsets via a software routine. This calibration procedure could be done throughout the day to compensate for any thermal or vibrational shifts in the raster scanner.